学步园

//passive.c 对tcp和udp通用

#include 
#include 
#include 
#include 
#include 
#include 

void error(int status, int err,char *fmt, ...) {
 va_list ap;
 va_start(ap, fmt);
 vfprintf(stderr, fmt, ap);
 va_end(ap);
 if(err)
  fprintf(stderr,":%s(%d)/n",strerror(err),err);
 if(status)
  exit(status);
}

static void  set_address(const char * hname, const char *sname, 
   struct sockaddr_in *sap, char *protocol) {
 struct servent *sp;
 struct hostent *hp;
 short port;
 bzero(sap, sizeof(*sap));
 sap->sin_family = AF_INET;
 if(hname != NULL) {
  if(!inet_aton(hname, &sap->sin_addr)) {
   hp = gethostbyname(hname);
   if(hp == NULL)
    error(1, 0, "unkown host %s", hname);
   sap->sin_addr = *(struct in_addr *)hp->h_addr;
  }
 }
 else
  sap->sin_addr.s_addr = htonl(INADDR_ANY);
 if (sp = getservbyname(sname, protocol))
  sap->sin_port = sp->s_port;
 else if ((sap->sin_port = htons((short)atoi(sname))) == 0)
           error(1,0,"unkown serivce  %s", sname);  
}

int server(char *hname, char *sname, char *protocol) {
 struct sockaddr_in local;
 int s,type;
 const int on = 1;
 if(strcmp(protocol,"tcp")==0)
  type = SOCK_STREAM;
 else
   type = SOCK_DGRAM;
 
 if((s=socket(AF_INET, type, 0)) <= 0)
  error(1, 0, "create socket failed!");
 set_address(hname, sname, &local, protocol);
 if(setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
  error(1,errno,"setsocket option failed!");
 if(bind(s,(struct sockaddr *)&local,sizeof(local)))
  error(1, errno, "bind failed!");
 if((type==SOCK_STREAM)&&listen(s,5))
  error(1, errno, "listen error!");
 return s;
}


//tcpserver.c  子进程

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
void process_server(int s, struct sockaddr_in * remote) {
     int len;
     time_t ti;
     char buff[128];
     printf("connection from: %s:%d/n",inet_ntoa(remote->sin_addr),ntohs(remote->sin_port));
      ti=time(NULL);
      //snprintf(buff,sizeof(buff),"%s/r/n",ctime(&ti));
 while((len=recv(s,buff,sizeof(buff),0))>0) {
  buff[len]='/0';
       send(s, buff,strlen(buff), 0);
  bzero(buff,sizeof(buff));
 }
}

void sig_child() {
 pid_t pid;
 int status;
 while((pid=waitpid(-1,&status,WNOHANG))>0)
  printf("%d terminated!/n",pid);
// while(wait(&status)>0);
}

int main(int argc, char **argv) {
    struct sockaddr_in remote;
    char *hname, *sname;
    int s, c, len;
    pid_t pid;
    if(argc < 2)
     error(1,0,"parameters less than 2");
    else if(argc == 2) {
     hname = NULL;
 sname = argv[1];
    }
    else if(argc == 3) {
     hname = argv[1];
 sname = argv[2];
    }
    s = server(hname, sname,"tcp");
    signal(SIGCHLD,sig_child);
    len = sizeof(struct sockaddr);
    while(1) {
     if((c=accept(s,(struct sockaddr *)&remote,&len))<=0){
  if(errno == EINTR)
   continue;
         error(1,errno,"accept error!");
 }
  if((pid=fork())>0) {
  close(c);
  continue;
 }
 else if(pid < 0)
  err(1,0,"fork error!");
 close(s);
     process_server(c,&remote);
 exit(0);
    }
    close(s);
    exit(0);
}

//tcpserver.c 用select

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
void sig_child() {
 pid_t pid;
 int status;
 while((pid=waitpid(-1,&status,WNOHANG))>0)
  printf("%d terminated!/n",pid);
// while(wait(&status)>0);
}


int main(int argc, char **argv) {
    struct sockaddr_in remote;
    char *hname, *sname;
    int s, c, len,fd;
    pid_t pid;
    fd_set rset,allset;
    int client[1024];
    int i,maxi,maxfd,nready;
    char buff[1024];
    if(argc < 2)
     error(1,0,"parameters less than 2");
    else if(argc == 2) {
     hname = NULL;
 sname = argv[1];
    }
    else if(argc == 3) {
     hname = argv[1];
 sname = argv[2];
    }
    
    s = server(hname, sname,"tcp");
    signal(SIGCHLD,sig_child);
    len = sizeof(struct sockaddr);
    
    FD_ZERO(&allset);
    FD_ZERO(&rset);
    FD_SET(s,&allset);
    maxi=0;
    maxfd=s;
    
    for(i=0;i<1024;i++)
     client[i]=-1;
 
    while(1) {
    
        rset=allset;
 
 if((nready=select(maxfd+1,&rset,NULL,NULL,NULL))<0)
  error(1,0,"select error!!");
 if(FD_ISSET(s,&rset)) {
      if((c=accept(s,(struct sockaddr *)&remote,&len))<=0){
          error(1,errno,"accept error!");
  }
  for(i=0; i<1024; i++) {
   if(client[i] != -1)
    continue;
   else {
    client[i]= c;
    break;
   }
  }

  if(i == 1024) 
   error(1,0,"too many clients!!");
  FD_SET(c,&allset);
  if(c>maxfd)
   maxfd = c;
  if(i > maxi)
   maxi = i;
  if(--nready==0)
   continue;
 }
        for(i=0;i<= maxi;i++){
 
  if((fd=client[i])==-1)
   continue;
  if(FD_ISSET(fd,&rset)){ 
   if((len=recv(fd,buff,sizeof(buff),0))>0) {
    buff[len]='/0';
         send(fd, buff,strlen(buff), 0);
    bzero(buff,sizeof(buff));
   }
   else {
    close(fd);
    FD_CLR(fd,&allset);
    client[i]=-1;
   }
   if(--nready==0)
    break;
  }
  }
     }
    close(s);
    exit(0);
}

//udpserver..c

#include 
#include 
#include 
#include 
#include 
#include 

void process_server(int s) {
     struct sockaddr_in remote;
     char buff[128];
     int len,n;
     while(1){
      n=recvfrom(s,buff,sizeof(buff),0,(struct sockaddr *)&remote,&len);
 //printf("%s,%d/n",buff,n);
 buff[n]='/0';
 sendto(s,buff,strlen(buff), 0, (struct sockaddr *)&remote,sizeof(remote));
     }
}

int main(int argc, char **argv) {
    struct sockaddr_in remote;
    char *hname, *sname;
    int s, c, len;
    if(argc < 2)
     error(1,0,"parameters less than 2");
    else if(argc == 2) {
     hname = NULL;
 sname = argv[1];
    }
    else if(argc == 3) {
     hname = argv[1];
 sname = argv[2];
    }
    s = server(hname, sname,"udp");
    process_server(s);
    close(s);
    exit(0);
}